Began his football career as a Blackpool FC trainee,
becoming the club's youngest first team player, aged 16 years and 170
days, signing professional forms a year later on 21 August 1990. Scored
fifteen goals in 115 league appearances before he broke the club's
transfer record for a fee received when signed for Queen's Park Rangers FC for
600,000 pounds on 12 August 1993. Scored sixteen goals in 168
league appearances. Sinclair signed for West Ham
United FC for 2.3 million pounds, plus Iain Dowie and Keith Rowland, on 30 January 1998. Despite
scoring 36 goals in 177 league appearances, relegation for the Hammers
meant he was offloaded to Manchester City
FC on 21 July 2003 for 3.3 million pounds. After 82 appearances and
five goals, he was released at the end of 2006-07. Cardiff City FC
signed Sinclair on 10 July 2007. Released from his contract on 21 May 2008,
four days after their FA Cup Final loss, he had scored once in 21
league appearances; Having returned to the Fylde coast, Sinclair was
assistant manager during the 2014-15 season for Lancaster City FC,
making one league substitute appearance.

FA Premier League Player of the Month October 1995;
BBC Match of the Day Goal of the Season 1996-97 (a
bicycle kick for Queen's Park Rangers FC vs. Barnsley FC, FA Cup fourth
round, 25 January 1997). PFA Division One Team of the Year
1996-97;

Due to the fact that
many matches rarely stuck to exactly ninety minutes long, allowing time
for injuries, errors and substitutions. The minutes here
given can only ever be a guideline and cannot therefore be accurate, only
an approximation.